Biomedical subjects

Jean Vanderpas

Publications and source records attributed to Jean Vanderpas.

5 recordsLinked to original sources

PubMed2003

Selenium supplementation at low doses contributes to the decrease in heart damage in experimental Trypanosoma cruzi infection.

Chagasic patients with cardiomyopathy have low levels of selenium (Se), a fundamental trace element. We evaluated the effect of supplementing infected mice with Se (0.25-16 ppm). Supplementation with 0.25 or 1 ppm Se led to parasitaemia and survival curves similar to those of the control group. Mice treated with 4-16 ppm showed a dose-dependent decrease of parasitaemia, significant for the highest concentration. This was probably due to a direct effect on the parasites, which were lysed after in vitro incubation with Se. Survival rates did not change significantly; however, heart damage was reduced in infected mice supplemented with 4 ppm Se, as indicated by a lower cardiac isoform of creatine kinase levels. Our results imply that Se supplementation does not lead to a general protection during infection, but may help protect the heart from inflammatory damage. The effect of Se supplementation in the course of T. cruzi infection depends on the host-parasite pair employed.

Acute Disease↗

PubMed2003

Selenium and iodine supplementation of rural Tibetan children affected by Kashin-Beck osteoarthropathy.

BACKGROUND: Kashin-Beck disease is an osteoarthropathy endemic in selenium- and iodine-deficient areas around Lhasa, Tibet. OBJECTIVE: We assessed the efficacy of selenium supplementation on disease progression. DESIGN: A double-blind, randomized controlled trial of selenium supplementation was carried out in 324 children aged 5-15 y who had Kashin-Beck disease. Two hundred eighty children received iodized oil before being randomly assigned to receive selenium or placebo, and a control group of 44 subjects was not supplemented at all. Clinical and radiologic signs, selenium status, urinary iodine, and thyroid function were evaluated at baseline and at 12 mo. RESULTS: The frequencies of joint pain, decreased joint mobility, and radiologic abnormalities were not significantly different between the 3 groups at 12 mo. Height-for-age z scores increased significantly in the subjects who received placebo and iodine or selenium and iodine. In contrast, unsupplemented control subjects did not recover from growth retardation. Serum selenium concentrations at 12 mo were within the reference range and were significantly greater in the selenium-iodine group than in the placebo-iodine group. Serum thyroid hormone concentrations were within the reference ranges after the administration of iodine, and these values were not significantly affected by selenium supplementation. CONCLUSIONS: The results of this study do not rule out the possibility that selenium may help to prevent the occurrence of Kashin-Beck disease. However, selenium supplementation had no effect on established Kashin-Beck disease, growth, or thyroid function once iodine deficiency was corrected. These results suggest that iodine, but not selenium, deficiency should be corrected in Tibetan children with Kashin-Beck disease.

Adolescent↗

PubMed2003

Trace elements, innate immune response and parasites.

Micronutrient deficiencies and infectious disease often coexist and show complex interactions leading to mutually reinforced detrimental clinical effects. Such a combination is predominantly observed in underprivileged people of developing countries, particularly in rural regions. Several micronutrients such as trace elements (zinc, iron, selenium) modulate immune function and influence the susceptibility of the host to infection. Nevertheless, the effect of individual micronutrients on components of innate immunity is difficult to design and interpret. Micronutrient deficiency, in general, has a widespread effect on nearly all components of the innate immune response. Chagas' disease is a pertinent model to study interaction of nutrition, immunity and infection, as it implies many components of innate immunity. An important question is whether alterations on micronutrient intake modify the course of infection. Some interactions of trace elements with innate immunity and acute inflammatory response are reviewed in this article with a special focus on selenium deficiency and Trypanosoma cruzi infection.

Acute-Phase Reaction↗

PubMed2002

Trypanosoma cruzi: host selenium deficiency leads to higher mortality but similar parasitemia in mice.

Selenium is an essential trace element and its deficiency was implicated in heart diseases. We recently showed low Se levels in chronic chagasic patients with cardiomyopathy. Herein, mice were depleted in Se by feeding the mothers with chow containing only 0.005 mg Se/kg and maintaining this diet for offspring, that were further infected with Trypanosoma cruzi. Survival rate was significantly lower in Se deficient than in control mice. Parasitemia was similar in all groups. Necrotic heart lesions were found after infection (high CK-MB levels). No outbreaks of parasite growth were detected in chronic survivors submitted or not to a second Se depletion. The present results confirm our hypothesis that a nutritional deficiency in Se is associated to a higher mortality during T. cruzi infection. The potential beneficial effect of Se supplementation is a perspective. Hypothesis to explain the higher susceptibility of Se-depleted mice to T. cruzi infection are discussed.

Animals↗

PubMed2002

Progressive Chagas' cardiomyopathy is associated with low selenium levels.

Selenium (Se) deficiency is linked with some cardiomyopathies. Its status was determined in 170 patients with chronic Chagas' disease from 2 Brazilian regions (Rio de Janeiro and Belo Horizonte), clinically stratified into groups as follows: indeterminate or asymptomatic (IND); cardiac asymptomatic (CARDa); cardiac symptomatic with moderate to severe heart dysfunction (CARDb); and healthy adults (HA), used for comparison. In most HA, Se levels were normal, excluding an overall Se deficiency. Se was significantly lower in CARDb than in HA, IND, or CARDa patients. This was not associated with a concomitant decrease in activity of glutathione peroxidase. Thyrotropin was normal, excluding iodine deficiency. Se correlated positive and significantly with ventricular ejection fraction (assessed via echocardiography). Asymptomatic children with acute Chagas' disease had normal Se as well as 5 noninfectious cases of cardiomyopathy. Low Se was found in 6 of 10 chagasic patients with digestive megasyndromes. Thus, the decrease in Se in chagasic patients seems to be a biological marker for Trypanosoma cruzi infection and related to the progression of pathology.

Animals↗